Multiuser MIMO CDMA Systems with Interference Cancellers in Rayleigh Channels
نویسنده
چکیده
In this paper, we deal with Multiple Input Multiple Output (MIMO) CDMA systems. We combine space time transmit diversity with interference cancellation detectors in case of Rayleigh channels and multiple receiving antennas. We analyze the BER performance of the proposed system over Rayleigh fading channels. The proposed system can be used in both up and down links. Simulation results show a significant suppression of Multiple Access Interference (MAI), a capacity improvement and a higher quality of transmission (lower BER). Performance comparison is made between the proposed system and existing MIMO detection algorithms as ZF and MMSE. We use Modified Space Time Spreading (MSTS) [7] as a MIMO strategy which provides additional gain over STS. Key-words: CDMA, multiuser detection, transmit diversity, MIMO
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